Former Vice Chairman and President of PetroChina Company Limited Jiang Jiemin attends a news conference in Hong Kong in this March 19, 2007 file picture. The trial of the former head of CNPC, China's top energy group, began on April 13, 2015 with charges

The trial of the former head of CNPC, China's top energy group, began on Monday, with charges of bribery, abuse of power and other corrupt practices making him the latest in a string of top officials hauled into court by an anti-graft campaign.

Scores of senior figures in the ruling Communist Party, the military and state-owned enterprises have been caught in President Xi Jinping's two-year war on corruption.

State television showed pictures of a grim-faced Jiang Jiemin, who also ran the state asset regulator for five months before being sacked in September 2013, standing in the dock with two policemen at his side.

He was formally charged last month.

Jiang was a close associate of Zhou Yongkang, the once-powerful domestic security chief and member of the elite Politburo Standing Committee, the most senior person to have been charged with corruption.

Zhou had also been at CNPC, the parent company of PetroChina Co. Ltd. , having risen through the ranks to serve as general manager from 1996 to 1998.

The Hanjiang Intermediate People's Court in Hubei province said on its official microblog that Jiang did not express any objections to the "facts about the crimes" he is accused of and did not defend himself when the evidence was presented.

The prosecutor "believes the facts about the crimes of the defendant Jiang Jiemin are clear, the evidence is certain and complete", the court said.

He needs to be held accountable under the law for his crimes, which include "bribery, not being able to account for a large number of assets and abuse of power by a staff member at a state-owned company", it added.

High-profile trials are typically held in places with little or no connection to the accused, to try and ensure judicial impartiality. However, the party controls the legal system, and a court is unlikely to challenge the accusations against him.

Cases usually take only a day or two to be heard, with a verdict delivered a few weeks later.

At least a dozen former associates and protégées of Zhou have been felled in Xi's graft crackdown.

Zhou was a patron of former high-flying politician Bo Xilai, who was jailed for life in 2013 for corruption and abuse of power in the worst political scandal in decades.

Zhou was arrested last year and expelled from the party, accused of crimes ranging from taking bribes to leaking state secrets. He will be tried in Tianjin, a city close to Beijing, though a date has yet to be set.